Tomaž Prosen – University of Ljubljana
Wednesday, October 11th, 10:45AM EDT (Zoom meeting starts at 10:30 EDT)
Exactly solved models of chaotic dynamics in quantum spin systems
I will discuss the problem of 'unreasonable effectiveness' of random matrix theory for description of spectral fluctuations in extended quantum lattice systems. A class of locally interacting spin systems has been recently identified where the spectral form factor is proven to match with random matrix theory, and where spatiotemporal correlation functions of local observables as well as some measures of dynamical complexity can be calculated analytically. These, so-called dual unitary systems, include integrable, non-ergodic, ergodic, and generically, (maximally) chaotic cases. After reviewing the basic properties of dual unitary Floquet circuits, I will argue that correlation functions of these models are generally perturbatively stable with respect to breaking dual-unitarity, and describe a simple result within this framework.